Such feed devices for needle looms are to feed a batt of staple fibers or endless fibers coming from a batt laying device in a possibly draft-reduced way to the first needle row of the needle loom for the subsequent needling operation. Drafts have harmful effects on the batt uniformity and thus on the batt quality. Each draft increases the differences in the mass distribution. Thick areas remain thick, thin areas are drawn even thinner.
A well known feed apparatus consists of an endless base conveyor band, on which the fiber batt is situated, an endless precompression conveyor band which is arranged above it and two so-called finger rollers, i.e. supply rollers, arranged downstream of said bands and having a plurality of circumferential grooves distributed in longitudinal direction of the rollers, in which plastic rings are slidably arranged at which fingers are formed, which extend in tangential direction of the rings in direction towards the needle loom and thus bridge over the gusset gap between the roller nip of the pair of finger rollers and the needle loom, more precisely the holding-down appliance and the needle board of the needle loom, so that the fiber batt in a compressed condition slides through these fingers, without suffering considerable drafts. A similar gusset gap bridge-over, which is formed by wires, which extend through grooves in the supply rollers, is described in U.S. Pat. No. 3,621,540.
These devices for feeding a fiber batt, however, have the disadvantage, that between the pre-compression device, which is usually formed of said two approaching endless conveyor bands, which are running over reversing rollers, as described above, and the finger rollers, upper and lower gusset gaps remain which have a triangular cross-section and which are not bridged-over, and into which the bulky fiber batt bulges in and thereby affect the fiber batt transport. The fiber batt elastically widened into the gusset gaps has to be drawn out of them, which results in the known disadvantageous drafts.
For the improvement of this situation it is already known to bridge-over the lower gusset gap, which is formed between the lower base conveyor band, running around a respective reversing roller, and the lower finger roller, by means of a transmission roller of a smaller diameter, which is situated in the gusset gap and essentially fills it. This transmission roller simply leans on the base conveyor band and the lower finger roller under friction and is supported by them at its total length, so that it cannot bend through. It is preferably driven individually, in order to release the fiber batt from the base band at its way from the base band to the lower finger roller and to transmit it to the finger roller. No solution has so far been offered for bridging-over the upper gusset gap, which remained between the pre-compression conveyor band and the upper finger roller.